Isoflavones In Women Research Articles

Development of an Assay for Soy Isoflavones in Women's Hair.

Soy isoflavones, at adequate dosages, have estrogenic and anti-thyroidal effects in animals and humans, which can either be beneficial or adverse, depending on the consumer’s physiological status. Hence, this study presents an assay of soy isoflavones in hair, aiming to give new information about a person’s exposure to isoflavones, when health issues related to estrogenic or thyroidal effects are observed. Aqueous or organic extraction procedures following acidic, basic, or enzymatic digestions were tested on 60 hair samples (from volunteers) from a hairdresser, and a clinical trial 2017T2-29. The acidic digestion method was the most efficient regarding isoflavones. A specific inquiry was developed to assess the dietary habits of French consumers based on the analysis of 12,707 food labels from France. It was used to check for the reliability of the new assay method. A score for the consumer exposures to isoflavones was built considering, among other parameters, soy-based diets and foodstuff containing soy as an ingredient, i.e., “hidden-soy”. The correlation between this score and isoflavone measurements in hair reached 0.947; p < 0.001. Therefore, providing that relevant data are considered to assess isoflavone exposure, hair that smoothens daily isoflavone intake variations, is a relevant tissue to assess human isoflavone exposure for subsequent health analyses.

Supplementary material for : Development of an assay for Soy Isoflavones in Women's Hair and validation of a French Dietary Habits Inquiry

Supplementary material for : Development of an assay for Soy Isoflavones in Women's Hair and validation of a French Dietary Habits Inquiry

Prevalence, sources, and predictors of soy consumption in breast cancer.

BackgroundA number of components in soy appear to have anticancer properties, including the isoflavones, genistein and daidzein. The use of soy by women with breast cancer is now being questioned because of the estrogen-like effects of isoflavones and possible interactions with tamoxifen. Clinicians providing nutrition counseling to these women are concerned because the availability of soy foods has increased dramatically in the past few years. The goal of this study was to quantify the intake of isoflavones in women with breast cancer.MethodsA cross-sectional study of 100 women with breast cancer treated at Cancer Treatment Centers of America® between 09/03 and 02/04. Each patient completed a soy food frequency questionnaire (FFQ) that was scored by Fred Hutchinson Cancer Research Center. Demographic and clinical predictors of soy intake were evaluated using one-way non-parametric Mann Whitney test and non-parametric spearman's rank correlation.ResultsMean age was 50.5 years (std. dev. = 9.4; range 31–70) and mean BMI was 27.3 kg/m2 (std. dev. = 6.75; range 17–59). Genistein and Daidzein consumption was limited to 65 patients with a mean intake of 11.6 mg/day (std. dev. = 21.9; range 0–97.4) and 7.6 mg/day (std. dev. = 14.1; range 0–68.9) respectively. Soy milk (37%) and pills containing soy, isoflavones, or "natural" estrogen (24%) were the two biggest contributors to isoflavone intake.ConclusionOur study suggests that the isoflavone intake of breast cancer patients at our hospital was quite variable. Thirty-five patients reported no soy intake. The mean daily intake of 11.6 mg genistein and 7.4 mg daidzein, is the equivalent of less than 1/4 cup of tofu per day. This amount is higher than what has been previously reported in non-Asian American women.

Association of Dietary Intake of Soy, Beans, and Isoflavones With Risk of Cerebral and Myocardial Infarctions in Japanese Populations

Soy and isoflavones have been proposed to reduce the risk of cardiovascular risk factors, but their potential as preventatives for cardiovascular disease remains uncertain. We investigated the association of soy and isoflavone intake with risk of cerebral and myocardial infarctions (CI and MI). To examine the association of soy and isoflavone intake with the risk of CI and MI, we studied 40,462 Japanese (40 to 59 years old, without cardiovascular disease or cancer at baseline). They completed a food-frequency questionnaire (1990-1992) and received follow-up to 2002. After 503,998 person-years of follow-up, we documented incidence of CI (n=587) and MI (n=308) and of mortality for CI and MI combined (n=232). For women, the multivariable hazard ratios and 95% confidence limits for soy intake > or = 5 times per week versus 0 to 2 times per week were 0.64 (0.43 to 0.95) for risk of CI, 0.55 (0.26 to 1.09) for risk of MI, and 0.31 (0.13 to 0.74) for cardiovascular disease mortality. Similar but weaker inverse associations were observed between intake of miso soup and beans and risk of cardiovascular disease mortality. The multivariable hazard ratios for the highest versus the lowest quintiles of isoflavones in women were 0.35 (0.21 to 0.59) for CI, 0.37 (0.14 to 0.98) for MI, and 0.87 (0.29 to 2.52) for cardiovascular disease mortality. An inverse association between isoflavone intake and risk of CI and MI was observed primarily among postmenopausal women. No significant association of dietary intake of soy, miso soup, and beans and isoflavones with CI or MI was present in men. High isoflavone intake was associated with reduced risk of CI and MI in Japanese women. The risk reduction was pronounced for postmenopausal women.

Implications of Gene-Environment Interaction in Studies of Gene Variants in Breast Cancer: An Example of Dietary Isoflavones and the D356N Polymorphism in the Sex Hormone-Binding Globulin Gene

Studies to identify common genetic variants contributing to breast cancer risk often yield inconsistent results. Breast cancer is a complex disease involving both genetic and environmental determinants. Dietary isoflavones are thought to reduce breast cancer risk by stimulating circulating sex hormone-binding globulin (SHBG) levels. The SHBG gene contains a D356N polymorphism and the N variant is associated with reduced SHBG clearance compared with the D variant. In this study, we show a significant gene-environment interaction between SHBG D356N polymorphism and dietary isoflavone exposure on circulating SHBG levels in 1,988 postmenopausal women. SHBG levels were positively associated with isoflavones in women carrying the N variant (etap2 = 1.9%; P = 0.006) but not in women carrying only the D variant (etap2 = 0.0%; P = 0.999; P(interaction) = 0.019). This finding shows that the subtle effects of some genetic variants may be magnified and only become detectable in the presence of certain exposures. This gene-environment interaction might explain heterogeneity in studies associating SHBG gene variants and soy consumption with breast cancer risk in Far East population exposed to high isoflavone levels compared with populations with lower levels.

A prospective survey evaluating the use of soy products in breast cancer

10562 Background: Many studies have evaluated the potential role of soy in the prevention of breast cancer. A number of components in soy appear to have anticancer properties, including isoflavones, genistein and daidzein. The use of soy by women with breast cancer is now being questioned because of the estrogen-like effects of isoflavones and possible interactions with tamoxifen. Clinicians providing nutrition counseling to these women are concerned because the availability of soy foods has increased dramatically in the past few years. The goal of this study was to quantify the intake of isoflavones in women with breast cancer to determine if their intake is of clinical significance. Methods: We evaluated a consecutive case series of 100 women with breast cancer treated at Cancer Treatment Centers of America between 09/03 and 02/04. After obtaining informed consent, each patient was asked to complete a soy food frequency questionnaire (FFQ) that was scored by Fred Hutchinson Cancer Research Center, the institute that developed and validated FFQ. Results: Mean age was 50.5 years (std. dev. = 9.4; range 31–70) and mean BMI was 27.3kg/m2 (std. dev. = 6.75; range 17–59). Table 1 shows detailed characteristics of our patients. Genistein and Daidzein consumption was limited to 65 patients with a mean intake of 81.5 mg/week (std. dev. = 153; range 0.02–682) and 52.9 mg/week (std. dev. = 98.8; range 0.02–482) respectively. Soy foods with highest reported consumption were soy sauce (37%), soy milk (23%), soy bars (18%), roasted soy nuts (13%) and tofu (13%). Conclusions: Our study suggests that the isoflavone intake of breast cancer patients at our hospital was quite variable. Thirty-five patients reported no soy intake. The mean daily intake translates into 11.6 mg genistein and 7.4 mg daidzein, which is equivalent of less than ¼ cup of tofu per day. This amount is slightly higher than what has been previously reported in non-Asian American women. [Table: see text] No significant financial relationships to disclose.

Risks and benefits of soy isoflavones for breast cancer survivors.

To present state-of-the-art information about the risks and benefits of soy isoflavones for breast cancer survivors. Published research articles, pertinent articles and books, and computerized databases. Some epidemiologic data suggest that soy isoflavones play an important role in preventing breast cancer in Asian women and promoting women's health in a variety of ways. However, the use of soy isoflavones in women with breast cancer is controversial. Risks and benefits exist regarding the use of soy isoflavones by breast cancer survivors. The use of soy isoflavones to promote health in breast cancer survivors remains controversial because of scant scientific data. Nurses should not only provide updated information to the public but also interpret research results carefully. More clinical trials need to be conducted on a longitudinal basis with the enrollment of breast cancer survivors.

The role of red clover (Trifolium pratense) isoflavones in women's reproductive health: a systematic review and meta‐analysis of randomised clinical trials

Focus on Alternative and Complementary TherapiesVolume 8, Issue 4 p. 544-544 The role of red clover (Trifolium pratense) isoflavones in women's reproductive health: a systematic review and meta-analysis of randomised clinical trials JS Thompson Coon, JS Thompson Coon Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this authorMH Pittler, MH Pittler Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this authorE Ernst, E Ernst Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this author JS Thompson Coon, JS Thompson Coon Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this authorMH Pittler, MH Pittler Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this authorE Ernst, E Ernst Complementary Medicine, Peninsula Medical School, Universities of Exeter and Plymouth, 25 Victoria Park Road, Exeter, EX2 4NT, UKSearch for more papers by this author First published: 14 June 2010 https://doi.org/10.1111/j.2042-7166.2003.tb04079.xCitations: 4Read the full textAbout ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume8, Issue4December 2003Pages 544-544 RelatedInformation

Randomized placebo-controlled trial of an isoflavone supplement and menopausal symptoms in women

Objective To test the hypothesis that increasing the intake of isoflavones by dietary supplementation may produce a therapeutic effect in reducing the incidence and severity of hot flushes in menopausal women.Methods Fifty-one postmenopausal women were randomized to placebo and active (one tablet per day of a 40-mg isoflavone supplement) groups in a cross-over design trial. After a 1-week run-in period, subjects were commenced on a 12-week period of treatment (active or placebo), followed by a 1-month placebo wash-out period, then crossed over to the alternative treatment regimen for a further 14 weeks. Symptom diaries were maintained throughout the trial and at the start and end of treatment. Plasma sex hormone binding globulin (SHBG) assay, full blood count, biochemical profiles, vaginal swabs and vaginal ultrasound scans were performed and isoflavones determined in 24-h urine collections by high-pressure liquid chromatography (HPLC) analysis.Results There was no significant difference between active and placebo groups in the reduction in hot flushes between start and finish time-points. Analysis performed on interim data time-points revealed a substantially greater reduction in flushing in the active group than placebo at 4 and 8 weeks after commencement of treatment, but this was not statistically significant. There were no significant differences between groups for Greene scores or in SHBG levels, hematological or biochemical parameters and vaginal swab or ultrasound findings. The combined values for all subjects, regardless of treatment group, revealed a strong negative correlation between the level of urinary isoflavone excretion and the incidence of hot flushes.Conclusions These data do not indicate a therapeutic benefit from dietary supplementation with isoflavones in women experiencing menopausal symptoms, but do indicate that the apparent placebo effect in many studies of menopausal symptoms may be attributable to dietary sources of isoflavones. The study also demonstrates that 3 months of isoflavone supplementation did not cause adverse events or endometrial changes.

Isoflavone Content of Breast Milk and Soy Formulas: Benefits and Risks

A recent editorial (1) properly credited Franke and Custer (2) for an important study of urinary and breast milk concentrations of isoflavones in women consuming soybeans. This editorial cited literature concerning potential health benefits of phytoestrogens and, to a much lesser extent, potential toxicity. In the accompanying letter below, Franke points out that infants consuming soy-based formula are exposed to high concentrations of phytoestrogens. Estrogens are two-edged swords in humans; both risks and benefits can be demonstrated in the same person. Two examples are oral contraceptives (benefit: fertility control; risk: increased incidence of breast cancer (3)) and unopposed estrogen replacement therapy (benefit: reduction in mortality due to heart disease and osteoporosis and relief of menopause symptoms; risk: increased incidence of endometrial cancer (4)). Given this characteristic of estrogens generally, what do we know of risks from phytoestrogens? Adverse effects of phytoestrogens on reproduction and development in wildlife (5), livestock (6), and experimental animals (7) have been documented. Developmental exposure to phytoestrogens results in toxicities similar or identical to those of other estrogens. Neonatal rodents have long been used as a model of human prenatal diethylstilbestrol (DES) exposure on the basis of developmental staging and similar outcomes from exposure (8). However, the neonatal rodent and postnatal human are not at equivalent morphological stages of development (9) and the neonatal rodent does not model the infant human. In addition to lacking a rodent estrogen model of the human infant, we also have little clinical experience with human infant exposure to estrogens generally. Although the data are limited for developmental effects of phytoestrogens, the similarity of DES and phytoestrogen effects in newborn rodents should be considered a cautionary note for the developmentally later exposure that occurs with soy infant formula. As the editorial points out, the beneficial effects of soy-based formulas or of …